1. Field
The present disclosure relates generally to testing equipment and in particular, to a method and apparatus for testing loop resistance in a vehicle. Still more particularly, the present disclosure relates to a method, apparatus, and computer program product for controlling a loop resistance tester, performing analysis of measured data, and integrating with data management tool/database.
2. Background
In aircraft, cable shielding is a component used for protecting various aircraft systems from electrical effects, such as lightning strikes, high intensity radiated fields, and other environmental conditions. Testing the cable shields and joints in aircraft systems may be performed using a loop resistance tester. A cable shield is the material that covers a number of wires in a cable. A cable shield may provide the wire protection from physical contact and/or from interference caused by electromagnetic fields or signals. A joint is a connection where a cable may be connected to another cable and/or device. A loop resistance tester is an electronic instrument or device for measuring the resistance of cable shielding and joints. A loop resistance tester may test this resistance cable shielding and impedance in joints as installed in aircraft in a manner that does not require the cables to be disconnected.
Typically, a loop resistance tester contains couplers, joint probes, and an instrument assembly. The couplers are used to measure the loop resistance formed by the shielding in the cable under test and the aircraft structure. The joint probes are used to measure the resistance of joints in the cable to ensure measured values are within designed tolerance and to compare the sum of joint impedances to the loop measurement, which includes all of the individual joints within the loop.
Maintenance personnel may test the cable shields and joints in various aircraft wire bundles. This type of testing may be performed on an aircraft that contains fuel and is totally non-intrusive when making these types of measurements.
Loop resistance testing of the shielding and the joints may be performed with the cable still installed. Loop resistance may be measured for a cable as well as a joint across which a connection may be made.
Presently, measurements of loop resistance involve a maintenance person placing the probes and couplers to cables and/or joints in selected locations of the aircraft. Thereafter, the maintenance person manipulates controls on a loop resistance tester to obtain measurements. These measurements are either written down or relayed via a radio or other communications device to another maintenance person for analysis. These types of interactions may be time-consuming and costly during maintenance operations.
Therefore, it would be advantageous to have a method and apparatus to overcome the problems described above.